Going to the regular spots along PCH will most likely be filled unless you have reservations(i.e, Sanddollar, Big Sur Campgrounds, willow creek, san simeon.) But if you want to go off the beaten path I suggest going to the overflow campground called Andrew Molera. It's a general parking lot where you have to hike your gear approx 1/4 mile to a campground field. The field is half way down the trail to the Beach where their are nice sandy beachs and Big sur River mouth. The best park of the rugged campground is that it's dirt cheap and usually not taken even on the weekends. I believe it's about 30 minutes south of Carmel if you are coming down from SF.

I haven't tried to fish there yet but plan to late August. If you fish out there let us know how it went. I bet the halibut are around there somewhere!

Best of luck